hwmon: (adm1029) fix checkpatch issues

fixed:
ERROR: space prohibited after that open parenthesis '('
+#define DIV_FROM_REG(val)	( 1 << (((val) >> 6) - 1))

WARNING: simple_strtol is obsolete, use kstrtol instead
+	long val = simple_strtol(buf, NULL, 10);

ERROR: do not use assignment in if condition
+	if ((err = sysfs_create_group(&client->dev.kobj, &adm1029_group)))

Signed-off-by: Frans Meulenbroeks <fransmeulenbroeks@gmail.com>
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>